The tissue culture core (Core B) will serve all projects in this program. Many studies proposed in these projects will require cultured neuronal cell lines or primary neurons. The personnel of Core B has considerable experience in growing and maintaining many different cell lines and strains. Our cell culture inventory consists of over 100 hybridoma cell lines that produce monoclonal antibodies to apolipoproteins, lipoprotein receptors, and other proteins, and about 50 cell lines that have been transfected with constructs that express different isoforms of apolipoprotein E, amyloid precursor protein, tau, or huntingtin or variants of each of these proteins. Core B will prepare the media and reagents used in culture studies, provide and maintain the equipment required for the preparation and growth of neuronal cultures, assist in transfection of different cell lines (e.g., Neuro-2a, B 103, C6, U87, HEK293T, and COS) with DNA constructs, perform the assay for quality control of recombinant apoE preparations, and assist in culturing primary neurons. The smooth operation of this core and the support it will provide for the proposed tissue culture studies is of fundamental importance to the successful outcome of this program project.